Aftermarket

Daimler Launches Production of DT12 Automated Manual Transmission

Daimler Trucks officials (from left) Ehrhard Thiel, manager for Gaggenau Powertrain Production; Frank Reintjes, head of Global Powertrain, Procurement and Manufacturing Engineering; and Matthias Jurytko, Gaggenau plant manager, with the new DT12 transmission where it is being assembled in Gaggenau, Germany. (Photo by Evan Lockridge)

GAGGENAU, GERMANY -- Managers at Daimler's Gaggenau, Germany, powertrain facility Monday proudly showed off how they are building the new Detroit DT12 automated manual transmission, which will be assembled here until it moves to Detroit brand headquarters in Redford, Mich., in 2015.

The 12-speed DT12 initially will be available exclusively in the Freightliner Cascadia equipped with a Detroit DD15 engine. The DT12 enhances fuel economy and performance for over-the-road/line-haul applications. Because it is designed to work with the DD15, fuel maps and the like are optimized, allowing for greater fuel savings than just those resulting from an automated manual, according to the company.

Officials said eventually 8-speed and 16-speed versions also would be available, and that it also at some point will be made available in other Daimler Trucks North America models.

Full production assembly of the DT12 into the Freightliner Cascadia is expected to begin May 6 at the company’s Cleveland, N.C, Freightliner Truck Manufacturing Plant.

The Redford assembly line will be built to duplicate the one in Gaggenau, and workers will be send to Germany for training. Frank Reintjes, head of Global Powertrain, Procurement and Manufacturing Engineering, Daimler Trucks, noted that with the launch of the heavy-duty engine platform, they followed a similar process in reverse when transferring the production from Redford to Mannheim, Germany.

The actual manufacture of the internal transmission gears, however, will remain in Gaggenau until the time when the Detroit plant has enough volume to make the investment in the very expensive machining equipment cost-effective.

The DT12

Officials at Daimler's Gaggenau transmission manufacturing facility emphasized the numerous quality checks on the product, including this test of a transmission gear. (Photo by Evan Lockridge)

The DT12 is based on the successful automated manual transmission that has been used in Europe, with the most recent version launched about two years ago in conjunction with the new Mercedes Actros truck. There are a few differences for the North American market, including 12-volt rather than 24-volt, a different electronic "brain" designed to communicate with the Detroit engine, and different bolt holes and a few other changes for actual installation in the chassis.

The DT12 combines the operational ease of an automatic with the efficiency of a manual transmission. Engineered for fuel economy, the DT12 includes innovative features such as eCoast (which allows the vehicle to coast down grades so the engine is operating at idle speed while maintaining momentum), skip shift, Active Driveline Protection and optional direct drive. The DT12 also has three driving modes that drivers can select based on terrain and application.

Brad Williamson, manager of engine and component marketing for DTNA, explained the benefits of skip-shifting: "They go from say 1 to 3 to 5 to 7, skip a gear very quickly, so the driver feels the performance is very aggressive. To get you into top gear faster where we're going to give you better fuel economy. It feels like you're taking off with a lot more power, a lot more torque response at the start. The faster we can get you in top gear, the longer we keep you in top gear, the better the fuel economy."

"Why all this?" Reintjes said. "It's all about fuel consumption reduction and better total cost of ownership."

"It's going to be a great product," Williamson said. "It's going to change the market in terms of what drivers accept. When power windows came out, when air conditioning came out, drivers and fleets in general said, 'We don’t need that.' But now they do. We think the DT 12 will be like that. It will make driving easier, and TCO is definitely affected by this product."

Acceptance of AMTs

Daimler believes the DT 12 AMT will help drive greater acceptance of automated transmission technology in North America. Currently, the North American market for automated manual transmissions is pretty low, at about 10 to 15%, said Daimler officials. They believe the DT12 can help change that, saying "a good two-digit market penetration figure is in sight," according to Reintjes.

He noted that six to seven years ago in Europe, manual transmissions made up about 70% of the market, automated about 30 percent. Within two years after Daimler making a push to the AMT, that proportion had flip-flopped to where AMTs made up about 70% of the transmission market, he said.

Not only do the AMTs save fuel for most drivers, but they also make driving easier, Reintjes said.

"The drivers understood, take out this trucker romance so to speak and you are just driving more relaxed. Specifically in Europe there are many applications where you drive down and up the alps you would have always to shift to meet the optimal rpm range, you're always busy, so you feel that as a driver in the evening."

The 12-speed DT12 accommodates all DD15 engine ratings from 455–505, with a 1550-1750 pounds-foot torque input. Additional versions of the DT12 for the Detroit DD13 and Detroit DD16 engines will be released in late 2013 and 2014. The transmission is part of the complete line of Detroit powertrain components that also includes Detroit engines and axles.

Click here for a photo gallery of gear-manufacture and transmission assembly at the Gaggenau plant.